NAME

       EVP_SIGNATURE-DSA - The EVP_PKEY DSA signature implementation

DESCRIPTION

       Support for computing DSA signatures. The signature produced with EVP_PKEY_sign(3) is DER
       encoded ASN.1 in the form described in RFC 3279, section 2.2.2.  See EVP_PKEY-DSA(7) for
       information related to DSA keys.

       As part of FIPS 140-3 DSA is not longer FIPS approved for key generation and signature
       validation, but is still allowed for signature verification.

   Algorithm Names
       In this list, names are grouped together to signify that they are the same algorithm
       having multiple names.  This also includes the OID in canonical decimal form (which means
       that they are possible to fetch if the caller has a mere OID which came out in this form
       after a call to OBJ_obj2txt(3)).

       "DSA", "dsaEncryption", "1.2.840.10040.4.1"
           The base signature algorithm, supported explicitly fetched with
           EVP_PKEY_sign_init_ex2(3), and implicitly fetched (through EC keys) with
           EVP_DigestSignInit(3) and EVP_DigestVerifyInit(3).

           It can't be used with EVP_PKEY_sign_message_init(3)

       "DSA-SHA1", "DSA-SHA-1", "dsaWithSHA1", "1.2.840.10040.4.3"
       "DSA-SHA2-224", "DSA-SHA224", "dsa_with_SHA224", "2.16.840.1.101.3.4.3.1"
       "DSA-SHA2-256", "DSA-SHA256", "dsa_with_SHA256", "2.16.840.1.101.3.4.3.2"
       "DSA-SHA2-384", "DSA-SHA384", "dsa_with_SHA384", "id-dsa-with-sha384",
       "1.2.840.1.101.3.4.3.3"
       "DSA-SHA2-512", "DSA-SHA512", "dsa_with_SHA512", "id-dsa-with-sha512",
       "1.2.840.1.101.3.4.3.4"
       "DSA-SHA3-224", "dsa_with_SHA3-224", "id-dsa-with-sha3-224", "2.16.840.1.101.3.4.3.5"
       "DSA-SHA3-256", "dsa_with_SHA3-256", "id-dsa-with-sha3-256", "2.16.840.1.101.3.4.3.6"
       "DSA-SHA3-384", "dsa_with_SHA3-384", "id-dsa-with-sha3-384", "2.16.840.1.101.3.4.3.7"
       "DSA-SHA3-512", "dsa_with_SHA3-512", "id-dsa-with-sha3-512", "2.16.840.1.101.3.4.3.8"
           DSA signature schemes with diverse message digest algorithms.  They are all supported
           explicitly fetched with EVP_PKEY_sign_init_ex2(3) and EVP_PKEY_sign_message_init(3).

   Signature Parameters
       The following signature parameters can be set using EVP_PKEY_CTX_set_params().  This may
       be called after EVP_PKEY_sign_init() or EVP_PKEY_verify_init(), and before calling
       EVP_PKEY_sign() or EVP_PKEY_verify(). They may also be set using EVP_PKEY_sign_init_ex()
       or EVP_PKEY_verify_init_ex().

       "digest" (OSSL_SIGNATURE_PARAM_DIGEST) <UTF8 string>
       "properties" (OSSL_SIGNATURE_PARAM_PROPERTIES) <UTF8 string>
           These two are not supported with the DSA signature schemes that already include a
           message digest algorithm, See "Algorithm Names" above.

       "nonce-type" (OSSL_SIGNATURE_PARAM_NONCE_TYPE) <unsigned integer>
       "key-check" (OSSL_SIGNATURE_PARAM_FIPS_KEY_CHECK) <integer>
       "digest-check" (OSSL_SIGNATURE_PARAM_FIPS_DIGEST_CHECK) <integer>
       "sign-check"  (OSSL_SIGNATURE_PARAM_FIPS_SIGN_CHECK) <int>
           The settable parameters are described in provider-signature(7).

       The following signature parameters can be retrieved using EVP_PKEY_CTX_get_params().

       "algorithm-id" (OSSL_SIGNATURE_PARAM_ALGORITHM_ID) <octet string>
       "digest" (OSSL_SIGNATURE_PARAM_DIGEST) <UTF8 string>
       "nonce-type" (OSSL_SIGNATURE_PARAM_NONCE_TYPE) <unsigned integer>
       "fips-indicator" (OSSL_SIGNATURE_PARAM_FIPS_APPROVED_INDICATOR) <integer>
           The gettable parameters are described in provider-signature(7).

SEE ALSO

       EVP_PKEY_CTX_set_params(3), EVP_PKEY_sign(3), EVP_PKEY_verify(3), provider-signature(7),

HISTORY

       DSA Key generation and signature generation are no longer FIPS approved in OpenSSL 3.4.
       See "FIPS indicators" in fips_module(7) for more information.

COPYRIGHT

       Copyright 2020-2024 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (the "License").  You may not use this file except
       in compliance with the License.  You can obtain a copy in the file LICENSE in the source
       distribution or at <https://www.openssl.org/source/license.html>.